Analog signal test circuit

Abstract

The present invention relates to an analog signal test circuit. The analog signal test circuit comprises: a plurality of analog signal input channels configured to receive an analog test signal; a channel gating circuit having an input end connected with the analog signal input channels and having an output end connected with an analog signal bus, wherein the channel gating circuit is configured to selectively connect or disconnect with the analog signal input channels; the analog signal bus connected with the channel gating circuit and connected with a buffer, wherein the analog signal bus isconfigured to transmit the selectively connected analog test signal to the buffer; and a buffer circuit having an input end connected with the analog signal bus and having an output end being the output end of the analog test signal, wherein the buffer circuit is configured to perform buffer and output on the analog test signal transmitted by the analog signal bus. The analog signal test circuitcan reduce the mutual interference between test nodes, can reduce the number of buffers and can ensure the high drive capability.

Description

technical field [0001] The present invention generally relates to the field of circuit testing, and specifically relates to an analog signal testing circuit. Background technique [0002] Electronic devices such as Micro Control Unit (MCU) and Embedded System (SOC) need to carry out their analog circuits and digital circuits respectively in the design stage, such as chip test (ChipProbing) and final test (Final Test) stage, and / or manufacturing stage. Tests to verify the functionality of individual modules or components. [0003] For digital circuit testing, the test circuit for MCU includes, for example, a scan chain, and the test circuit for internal memory includes, for example, BIST (Built-in Self Test). [0004] For the analog circuit test, there is no relatively complete test circuit or test method at present. The main test method currently used is to directly input the analog signal excitation, and then measure the output analog signal. However, such a testing appr...

AI Technical Summary

Problems solved by technology

[0005] (1) There are mutual influences between the various analog modules, for example, the current may pass through the switch circuit, which will cause noise problems in the analog test, affect the test accuracy, and the test efficiency is low; and

[0006] (2) Since the driving ability of key test nodes is generally weak, if the test node directly outputs, the amplification ability is low, which directly makes it difficult to directly observe. Therefore, it is generally necessary to attach a buffer to each test node to amplify the test node. analog nodes, which results in higher circuit cost and larger circuit area

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